Starting-crank



A. M. MORTON AND L. A. COZART. STARTING CRANK. APPLICATION men JUNE 11. ms.

1,356,876. Patented Oct. 26,1920.

2 SHEETS-SHEET l.

A. M. MORTON AND L. A. COZA RT.

STARTING CRANK.

APPLICATION FILED JUNE 1|, 1919.

Patented 0013. 26, 1920..

2 SHEETS-SHEET 2.

UNITED STATES PATENT OFFICE. g

ALFRED M. MORTON AND L'U'TI-IER A. COZART, 01 LITTLE ROCK,

STARTING-CRANK.

Specification of Letters Patent. Pate t d O t '26 1'920 Application filed .Tune 11, 1919. .Serial No. 303,296.

To all w ham z'tmay concern:

Be it known that we, ALFRED M. MORTON and LUTHER A. COZART, citizens of the United States, residing at Little Rock, in the county of Pulaski and State of Arkansas, have invented certain new and. useful. Improvements in Starting-Cranks, of which the following is a specification.

The invention provides a starting crank for overcoming the inertia of an internal combustion engine, whereby the initial move ment essential may be imparted by hand power in a mamier well understood. The invention aims to provide a starting crank which will not fiy backward upon premature starting or back fire of the engine and cause injury to the operator, such as frequently occurs from a back lire when the ignition is advanced to cause explosion before a piston reaches the limit of its forward stroke in the cylinder. 7 v

The present invention provldes a starting crank particularly'adapted for motor vehicles, whereby'the same may be started by hand without injury or fear on the part of the operator, since in the event. of a back fire, the crank will'be held'against backward movement.

The drawings illustrate a preferred embodiinent of'the invention. Howeven it is to be understood that in adapting the same to meet different conditions, various changes in the form, proportion, and minor details of construction may be resorted to without departing from the nature of the invention as claimed hereinafter.

Referring to the drawings herewith Figure 1 illustrates a starting crank in elevation, the same being constructed inaccordance with and embodying the essential features of the invention.

Fig. 2 is a front view.

Fig. 3 is a side view, parts being broken away and the bearing being. in sectiony.

Fig. 4 is a sectional detail on the line 14 of Fig. 2 looking to the left, as indicatedby the arrow.

Fig. 5 is a sectional detail on the line 5 -5 of Fig. 3 looking in the direction of the arrows. 4

Fig. 6 is a section on the line 6-6 of Fig.

V 3 looking in the direction of'thearrows.

Fig.7 is a sectionaldetail on the-line 7- -7 of Fig. 3 looking to the right, as indicated by the arrows, the dotted lines indicatingthe shaft 2.

rim of the bearing in which the complemen tal parts of the starting crank are mounted. Fig. 8 is a sectional detail showing more clearly the means whereby the dog is released from the detent cooperating therewith to hold it out of action. 7

Corresponding and like parts are referred to in the following description and indicated in the several views of the drawings by like reference characters. I The starting crank comprises essentially a crank 1 and a shaft 2. These two parts are adapted to be operatively connected by means of a ratchet mechanism, which in the event of a back fire is automatically uncoupled so thatthe shaft 2 may turn with the engine shaft without rotating the crank 1 in a reverse direction. Suitable mechanism is provided for positively preventing backward rotation of the crank. The crank 1 is provided with a sleeve 3 which receives an end of the shaft 2 and with a disk at. These elements form an integralpart of the crank.

fastening 6 connects the crank to the shaft and preferably consists of a machine screw which passes loosely through the. crank and has screw-thread engagement with the.

A suitable bearing receives the starting crank and comprises a rear wall 7 and a rim 8. vThe wall 7 is centrallyapertured and is provided with aninwardly extending boss 9 in which the innerend of the sleeve 3 is mounted. The disk a snugly fits within the outer or open end of the rim 8 and closes the same. -A shoulder 10 formed onthe shaft 2 engages the outer side 0mm wall ,7 and the adjacent end of the sleeve 3 and prevents V outward movement ofthe starting crank.

Thesleeve 3 is provided upon opposite sides with spaced earsll and .12. A dog 13' is pivotally supported between the ears V 11 and is of approximately u shape. One

end of the dog, 18 is reduced and pivotally supports a pawl 14; which-is adapted to en gage ratchet teeth 15 formed upon the inner of the crank 1, that is,-.in' a direction to crank 1 in'a reverse direction isprevented I side of the rim 8. In the forward rotation by engagement of the pawl 14 with the teeth 15 and by reason of the inclination of the pawl 14, the end of the dog carrying the same is pressed inward when the crank 1 tends tomove backward, thereby automatically disengaging the crank 1 from the shaft 2, which latter is clutched to the shaft of the engine in the usual way. When the end of the dog 13 carrying the pawl 14 is pressed inward it is retained in such position by means of a detent 16 which is pivoted between the ears 12. The opposing ends of the dog 13 and detent 16 are formed with engaging elements shown most clearly in Figs. 6 and 7 which are adapted to ride one upon the other and become coupled, thereby holding the dog 13 clear of the shaft 2 so that said shaft may rotate freely in a reverse direction in the event of a back fire.

The dog 13 is provided at one end with a tooth 17 which is adapted to engage one of a number of notches 18 formed in a side of the shaft 2, whereby the crank 1 and shaft 2 rotate together when giving the initial movement to the engine for starting the same. The sleeve 3 is formed in its sides with openings to admit of the toothed end 17 of the dog engaging the notches 18. A spring 19 secured at one end to an ear 11 has its opposite end engaging a pin 20 projecting from a side of the dog 13 and this sprin normally tends to press the toothed' end 1! of the dog into engagement with the shaft 2. A spring 21 of helical contractile form is secured at one end to an ear 11 and at its opposite end to the detent 16 and normally tends to hold the toothed or engaging end of the detent 16 in the path of the toothed or engaging end of the dog 13. A spring 22 secured at one end to the dog 13 has its opposite end in engagement with the pawl 14 and normally acts to hold the end of the pawl 14 in engagement with the toothed rim of the bearing.

The detent 16 is provided with a lateral projection 23 which is adapted to cooperate with a plunger 24 yieldably mounted in an extension of the disk 1. The inner end of the plunger 24 is made rounding so as to ride upon the beveled end of the projection 23 and effect an outward movement of the toothed end of the detent 16, whereby to disengage the detent from the dog when it is required that the dogshould clutchingly engage the shaft 2 as when cranking the engine. The plunger 24 is normally pressed outward by means of an expansible helical spring 25 mounted thereon and exerting an outward pressure.

The bearing is adapted't'o be secured to the frame work in any manner and-is shown as provided with wings 26 for this purpose. When a starting crank embodying the in-. vention is applied to an internal combustion engine it is adjusted so that the shaft 2 is in clutched engagement with the shaft of the engine. When it is required to start the engine, the-parts occupy the position substantially as shown in Fig. 6, that is, with the dog 13 in clutched engagement with the shaft 2. Rotation of the crank 1 in a clockwise direction causes corresponding rotation of the shaft 2. During this operation the pawl 14: rides upon the teeth 15 of the bearing. In the event of aback fire of the engine due to premature explosion, the shaft 2 rotates in a counter-clockwise direction and presses the toothed end 17 of the dog 13 outward and the opposite end of the dog 13 provided with the pawl 14: inward and said end automatically engaging the detent 16, holds the toothed end 17 of the dog 13 clear of the shaft. Backward rotation of the crank is prevented by the pawl 14 holding fast against the tooth 15 with which it happens to be in engagement. Before the shaft 2 can be turned forward by means of the crank 1 it is necessary to release the dog 13 so that its toothed end 17 may engage a notch of theshaft 2. This is accomplished by pressing the plunger 24; inward which causes the inner rounded end of the plunger 24 to ride upon the beveled end of the projection 23 which moves the toothed end of the detent 16 outward, thereby releasing the dog 13 which is thrown into operative position by means of the spring 19 in the manner herein stated. f

The foregoing description and the drawings have reference to what may be considered the preferred, or approved form of our invention. It is to be understood that we may make such changes in construction and-arrangement and combination of parts,

materials, dimensions, et cetera, as may prove expedient and fall within the scope of the appended claims.

Having thus fully described our invention, what we claim as new and desire to secure by Letters Patent is 1. In a starting crank, embodying a crank and a shaft, a sleeve forming a part of the crank and receiving an end of the shaft, a dog mounted upon the sleeve and rotatable with the crank and having a toothed end to engage the shaft and cause it and the crank to rotate in one direction, a detent mounted upon said sleeve and adapted to engage the dog and hold it clear of the shaft, whereby the latter is adapted to rotate freely in both directions and a plunger mounted upon the crank to effect disengagement of the detent from the dog to admit of the latter automatically engaging the shaft when it is re- I quired to start the engine. a

the latter is adapted to rotate freely in both directions, a plunger mounted upon the crank to effect disengagement of the detent from the dog to admit of the latter automatically engaging the shaft when it is required to start the engine, and means for preventing backward rotation of the crank, the same consisting of a pawl pivotally mounted upon the dog and a toothed element concentrio with the shaft and adapted to have the pawl ride upon the teeth thereof in the for ward rotation of the crank.

3. In a starting crank, embodying a crank and a shaft, a sleeve forming a part of the crank and receiving an end of the shaft, said sleeve having openings in its sides and the shaft being provided in its sides 7 with.

notches to register with the openings of the sleeve, a dog mounted upon the sleeve and having a toothed end to enga e the notches of the shaft in the forward rotation of the crank and to ride out of said notches in the backward rotation of the shaft, a detent mounted upon the sleeve and adapted to automatically engage the dog and hold its toothed end clear of the shaft, means mounted upon the crank to effect disengagement of the detent from the dog and means for preventing backward rotation of the crank without interfering with its free forward rotation.

4:. In a starting crank, embodying a crank and a shaft, a sleeve forming a part of the crank and receiving an end of the shaft, said sleeve having offstanding ears and intermediate openings, the shaft having notches in its side in the plane of the openings of the sleeve, a dog pivotally mounted upon one of the ears and having a toothed portion to clutchingly engage the shaft, a detent pivotally mounted upon another car and adapted to engage the dog and hold it clear of the shaft, means mounted upon the crank to effect disengagement of the detent from the dog and a ratchet mechanism for preventing backward rotation ofv the crank without interfering with its free forward rotation.

5. In a starting crank, embodying a crank and a shaft, asleeve forming a part of the crank and receiving an end of the shaft, a

dog mounted upon the sleeve and rotatable with the crank and having a toothed end to engage the shaft and cause it and the crank to rotate in one direction, a detent mounted upon said sleeve and adapted to engage the dog and hold it clear of the shaft, a projecti'on extending laterally from the detent and a plunger yieldably mounted upon the crank and adapted to engage the said projection and effect disengagement of the detent from the dog.

6. A starting crank, comprising a bearing embodying a wall and a rim, the latter being internally toothed, a crank provided with a sleeve and a disk, the sleeve being' mounted in the wall of the bearing and the disk closing the front of the rim and fitting snugly therein, a shaft having an end portion mounted in the sleeve and provided with a shoulder to engage the outer face of the bearing and the adjacent end of the sleeve, connecting means between the crank and shaft, a dog pivotally mounted upon the sleeve and adapted to clutchingly engage the portion of the shaft mounted therein, a detent mounted upon the sleeve and adapted to engage the dog and hold it clear of the shaft, a pawl pivotally mounted upon the dog and adapted to engage the toothed portion of the rim, and a plunger mounted upon the crank and adapted to effect disengagement of the detent from the dog.

In testimony whereof weafiix our signatures in presence of two witnesses.

ALFRED M. MORTON. LUTHER A. COZART.

\Vitnesses:

CLARENCE FREnmcKsoN, W. T Oonnsnv. 

